Add placeholder property for line_edit

this useful for user input tip

scene/gui/line_edit.cpp

@@ -108,7 +108,7 @@ void LineEdit::_input_event(InputEvent p_event) {
 				selection.doubleclick=false;
 
 				if (OS::get_singleton()->has_virtual_keyboard())
-					OS::get_singleton()->show_virtual_keyboard(get_text(),get_global_rect());
+					OS::get_singleton()->show_virtual_keyboard(text,get_global_rect());
 			}
 
 			update();
@@ -634,14 +634,19 @@ void LineEdit::_notification(int p_what) {
 			Color font_color_selected=get_color("font_color_selected");
 			Color cursor_color=get_color("cursor_color");
 
+			const String& t = text.empty() ? placeholder : text;
+			// draw placeholder color
+			if(text.empty())
+				font_color.a *= 0.6;
+
 			while(true) {
 
 		//end of string, break!
-				if (char_ofs>=text.length())
+				if (char_ofs>=t.length())
 					break;
 
-				CharType cchar=pass?'*':text[char_ofs];
+				CharType cchar=pass?'*':t[char_ofs];
-				CharType next=pass?'*':text[char_ofs+1];
+				CharType next=pass?'*':t[char_ofs+1];
 				int char_width=font->get_char_size( cchar,next ).width;
 
 		// end of widget, break!
@@ -678,7 +683,7 @@ void LineEdit::_notification(int p_what) {
 			}
 
 			if (OS::get_singleton()->has_virtual_keyboard())
-				OS::get_singleton()->show_virtual_keyboard(get_text(),get_global_rect());
+				OS::get_singleton()->show_virtual_keyboard(text,get_global_rect());
 
 		} break;
 		case NOTIFICATION_FOCUS_EXIT: {
@@ -938,6 +943,17 @@ String LineEdit::get_text() const {
 	return text;
 }
 
+void LineEdit::set_placeholder(String p_text) {
+
+	placeholder = p_text;
+	update();
+}
+
+String LineEdit::get_placeholder() const {
+
+	return placeholder;
+}
+
 void LineEdit::set_cursor_pos(int p_pos) {
 
 	if (p_pos>(int)text.length())
@@ -1223,6 +1239,8 @@ void LineEdit::_bind_methods() {
 	ObjectTypeDB::bind_method(_MD("select_all"),&LineEdit::select_all);
 	ObjectTypeDB::bind_method(_MD("set_text","text"),&LineEdit::set_text);
 	ObjectTypeDB::bind_method(_MD("get_text"),&LineEdit::get_text);
+	ObjectTypeDB::bind_method(_MD("set_placeholder","text"),&LineEdit::set_placeholder);
+	ObjectTypeDB::bind_method(_MD("get_placeholder"),&LineEdit::get_placeholder);
 	ObjectTypeDB::bind_method(_MD("set_cursor_pos","pos"),&LineEdit::set_cursor_pos);
 	ObjectTypeDB::bind_method(_MD("get_cursor_pos"),&LineEdit::get_cursor_pos);
 	ObjectTypeDB::bind_method(_MD("cursor_set_blink_enabled", "enable"),&LineEdit::cursor_set_blink_enabled);
@@ -1257,6 +1275,7 @@ void LineEdit::_bind_methods() {
 	BIND_CONSTANT( MENU_MAX );
 
 	ADD_PROPERTYNZ( PropertyInfo( Variant::STRING, "text" ), _SCS("set_text"),_SCS("get_text") );
+	ADD_PROPERTYNZ( PropertyInfo( Variant::STRING, "placeholder" ), _SCS("set_placeholder"),_SCS("get_placeholder") );
 	ADD_PROPERTYNZ(PropertyInfo(Variant::INT, "align", PROPERTY_HINT_ENUM, "Left,Center,Right,Fill"), _SCS("set_align"), _SCS("get_align"));
 	ADD_PROPERTYNZ( PropertyInfo( Variant::INT, "max_length" ), _SCS("set_max_length"),_SCS("get_max_length") );
 	ADD_PROPERTYNO( PropertyInfo( Variant::BOOL, "editable" ), _SCS("set_editable"),_SCS("is_editable") );

scene/gui/line_edit.h

@@ -67,6 +67,7 @@ private:
 
 	String undo_text;
 	String text;
+	String placeholder;
 
 	PopupMenu *menu;
 
@@ -135,6 +136,8 @@ public:
 	void delete_text(int p_from_column, int p_to_column);
 	void set_text(String p_text);
 	String get_text() const;
+	void set_placeholder(String p_text);
+	String get_placeholder() const;
 	void set_cursor_pos(int p_pos);
 	int get_cursor_pos() const;
 	void set_max_length(int p_max_length);